The goal of this project is to develop a very high-speed (1 billion cells/hour) cell sorting system with hierarchical architecture using multiple markers to achieve ultra high purity (99.999 percent) Hematopetic Stem Cells (HSC) samples derived from adult peripheral blood or bone marrow and their precursor Mesenchymal Stem Cell (MSC) samples derived from adult bone marrow. HSC/MSC derived from adult sources circumvent the ethical issues surrounding the use of embryonic stem cells while holding the promise for cell replacement therapies for diseases such as diabetes, Parkinson's Disease, spinal chord injury, and many others. Specific aims of Phase 1 of this project are: 1. Develop overall architecture of the high-speed cell sorter including the sub-systems for optics, data acquisition and control. 2. Demonstrate the feasibility of single channel switching speed of 2,000 cells/second. 3. Develop the design of micro-fabricated parallel channel array-chip, Gigasort, to achieve sorting speed of 1 billion cells/hour. 4. Develop a plan for test and validation of Teragenics' high-speed cell sorter including preliminary experimental protocols for use with specific cell markers. The core of the proposed cell sorter comprises of a microfluidic chip, Gigasort (Teragenics patent pending), which takes advantage of a rapid switching methodology coupled with a high degree of parallelism to enable the cell sorting at high speeds and a hierarchical approach to sorting to enable high sorting purity. The Gigasort chips are manufacturable using high volume microfabrication techniques and are low cost and disposable. The Gigasort chip interfaces with instrument sub-systems for optical detection and readout, control electronics, reagent storage etc and works with multiple positive and negative markers for HSC/MSC such as CD34, CD34+, Sca+, Lin-in a single hierarchical sort. The proposed project will deliver the blue print for the high speed cell sorter that delivers 3 orders of magnitude purer HSC/MSC samples 4 times faster than available methods with a cost model that allows the Gigasort microfluidic chip to be disposable, thus maintaining a fully sterile environment for clinical applications.